Patent GB-851651-A (GB)
Title: Polyphenyl ether compositions and their use as lubricants
IPC: C07C391/02
Filed: 1958-12-08
Abstract: The invention comprises a mixture of two or more compounds of general formula:  <FORM:0851651/IV(b)/1> where A is oxygen, sulphur, selenium or isopropylidene, at least 1/3 of the A's being oxygen atoms and not more than 1/3 being sulphur and/or selenium atoms, each n represents the number of substituent groups B attached to the phenyl radicals and may be O, B is tertiary butyl or alpha cumyl and at least 1/3 of the linkages A between the phenyl radicals, present in the whole mixture are in the meta position relative to another such linkage. Preferably the mixture of polyphenyl ethers has an average of 3-8 phenyl radicals per molecule, and preferably 40-100% of the linkages A are oxygen atoms and any remaining linkages A are isopropylidene radicals.  It is also preferred that the mixture consists of at least 50% of components wherein all the A's are in meta positions relative to each other or consists of at least 60% of components wherein at least 2/3 of the A's are in meta positions relative to each other. Typical polyphenyl ethers which may be present in the mixtures are bis(meta, para, and ortho-phenoxyphenyl) ethers, meta and para-bis(meta and para-phenoxy-phenoxy)benzene, meta(meta-phenoxyphenoxy)(meta-tert.butylphenoxyphenoxy) benzene, and meta (metaalpha - cumylphenoxyphenoxy) (meta - phenoxy - phenoxy) benzene.  A mixture of m-bis(m-phenoxyphenoxy)benzene with ortho and/or para isomers thereof may be used, the mol ratio of the meta ether to the other ethers being between 1:2 and 9:1. The mixtures may be obtained by simple mixing of the components but are conveniently obtained by reacting a mixture of alkali metal phenates with an appropriate monoor di-bromo-aryl compound, or by reacting a single alkali metal phenate with a mixture of mono- and/or dibromo aryl compounds.  The reaction may be effected by heating the reactants for 0,5 to 10 hours at 150-300 DEG C.  A copper catalyst may be present. Included in specified phenates are potassium meta-phenoxyphenate, potassium meta alpha-cumyl phenate, sodium meta-phenoxy (para-tert. butyl phenate), the sodium salt of p-hydroxy diphenyl thioether, and the potassium salt of m-hydroxy diphenyl selenide.  Included in specified bromo aryl compounds are 1-alpha cumyl-3-bromobenzene, dimethyl (m-tert.-butylphenyl)(m-bromophenyl) methane, phenyl (m-bromophenyl)ether, o, m, and p-dibromobenzenes, 1-tert. butyl-3,5-dibromobenzene, and 1-alpha cumyl-3,4 or 2,5, or 3,6, or 4,6, or 3,5-dibromobenzene.  The mixtures may be used as lubricants, heat exchange fluids, or hydraulic fluids.ALSO:A mixture of two or more polyphenyl ethers having the formula:  <FORM:0851651/III/1> (wherein the A's stand for oxygen, sulphur, or selenium, or for isopropylidene, at least 1/3 of the A's being oxygen atoms and not more than 1/3 being sulphur and/or selenium atoms, each n being the number of substituent groups attached to the phenyl radicals and being zero or a whole number, the B's representing tertiary butyl or alpha-cumyl groups, and at least 1/3 of the linkages A in the whole mixture being in meta position relative to another such linkage) are used as lubricants in engines operating at high temperatures such as aircraft and gas turbine engines, and also as lubricants, heat exchanger fluids or hydraulic fluids in radiation-emitting apparatus. Polyphenyl ether mixtures having an average of 3-8 phenyl radicals per molecule are preferred.  Specified polyphenyl ethers which may be present in the mixtures are bis(meta, para, and ortho-phenoxyphenyl) ethers, meta and para-bis(meta and para-phenoxyphenoxy) benzenes, and m(m-alpha-cumylphenoxyphenoxy) (m-phenoxyphenoxy) benzene.  A mixture of m-bis(m-phenoxyphenoxy) benzene with o- and/or p-isomers thereof may be used, the mol ratio of the meta ether to the other ethers being between 1:2 and 9:1.  The mixtures may be obtained by simple mixture of the components or by reacting suitable alkali meta-phenates with a mixture of mono- and/or dibromo aryl compounds. The polyphenyl ether mixtures may be used alone or with additives such as pour-point depressants, anti-oxidants, anti-corrosive agents, viscosity index improvers, anti-lacquering agents, and extreme-pressure additives.  Specified additives include polymers of esters of acrylic, methacrylic, and other 2-alkyl acrylic acids; salts of aromatic carboxylic acids (e.g. alkyl salicylic acids) or of phenols (including alkylamino and other substituted phenols) with Group II metals; trialkyl, triaryl, and trialkaryl phosphates, and halo-alkylphosphonates such as monobutyl hydrogen trichloromethyl-phosphonate and its amine salts e.g. its salt with di(2-ethylhexyl) amine.